Yellowing/brown spotting along the leaves.

[Cornsage]

Hello again! The last couple of days my partner and I have noticed some yellowed/browning along the edges of a couple of our GSC leaves. I am not sure if overwatering is an issue as we let the soil dry and water about every 3-4 days, or when the leaves begin to droop.

My next thought was Nitrogen Toxicity, but the first time we fertilized was on 7/11 with Fox Farm's "Grow Big" liquid plant food (6-4-4). We use bottled water with our plants and use about 1/8 teaspoon/cup. Each plant gets about 1 cup each with very minor drainage from the bottom.

Then we watered again (no nutes) on 7/15 as they began to droop again. We also noticed that the humidity was too high as the Dehumidifier was not draining properly (this has been fixed)

Around 7/17 the plants were needing water again but I didn't want to risk overwatering as I wanted to feed them again. This is when I also began to notice some yellowing and browning on the edges of a couple of leaves. The very pointed tips had also started to curl/point downward as well.

7/18 We fertilized again with the same measuring as 7/11. Next watering (no nutes) would be on 7/21 or 7/22 depending on how dry they get.

The images below were just taken prior to this post. Would this schedule lead up to toxicity? FF's General Feeding guidelines state to feed every other watering.

We had some issues with Spider mites about a month ago, but after some neem oil spray solution that pretty much gotten rid of them, and any stragglers since I squashed. We have not seen any for a few weeks now. I also dusted the topsoil with some Diatremetrius Earth on 7/16 just as a precaution. We had also trimmed up the lowest leaves to prevent the mites from settling as well on 7/11.


Here in the Midwest, the highs outside have been about 95s and very dry. There is an AC, humidifier and dehumidifier in the tent. Our Temperature range is about 75-80 degrees F (plus or minus a 2/3 degrees) with our general humidity being about 60% on average.


I don't think it's root rot as, again, I try to let it dry out before watering, but a couple of articles suggest that if the plants wilt more frequently I may have to add more water or water more frequently, but again, after 1 cup, there is some leakage from the bottom.

So far I notice these features on the lowest leaves, in the meantime, should I leave them or remove them?

Also, we transplanted them from solo cups to the current 3-gallon pots on 6/28. Could this be a sign that we need to transplant them to their final 5 gallon home, or should we wait? My plan was to transplant them on 7/25 (and then feed them right afterwards) and then switch them to Bloom on 8/6 as they'll be 60 days old then.

[F10werChyld]

I'm guessing but I think you are under-watering. You are putting 1 cup of liquid into a 3 gallon pot, sounds a little conservative. I think the rec on the website where all the knowledge lives is to shoot for about 20% runoff? This is a good guide: https://www.growweedeasy.com/how-often-water-marijuana

[Tersky]

Looks like nitrogen toxicity to me along with some possible ph or root issue. Seeing a dark green and downward claw like leaf structure is textbook nitrogen tox. https://www.growweedeasy.com/cannabi...rogen-toxicity

Signs of Nitrogen Toxicity

• Dark green leaves and foliage
• Leaf tips may turn down, without signs of overwatering.
• You may notice yellowing on the affected leaves or other signs of nutrient deficiencies as time goes on
• Nitrogen toxicity is often but not always accompanied by nutrient burn
• The Claw often seems random, affecting leaves here and there
• Heat and pH problems will make the clawing worse, as they stress out the plant and lower her defenses, and cause her to drink more water (and uptake more N)
• As time goes on, the claw leaves will eventually start turning yellow, getting spots, and dying

[Jordann]

When you say water comes out the bottom when giving a cup I think it follows the edge of the pot or has a fast way down. 3 gallon pot give it a gallon of water. I have 10 gallon fabric pots and I put 4 gallons every 3 days. If you're worried about giving more and over watering then put more holes in your buckets. They love their oxygen at the roots. I don't have a better picture but this should give an idea. This is a one gallon pot and I slowly put one gallon of water through every couple days. You would love fabric pots. It's like day and night.

Id say under watering and wouldn't have to worry about over feeding. They don't need to be transplanted yet they still have room to spread their roots. Based on size of plant compared to size of pot.

Never assume the maker will put enough holes in the pot. Some plants like moist soil but pot likes oxygen at the roots, holes holes and more holes. Bottom and up the sides lol.

[Ckbrew]

Nitrogen toxicity. Flush with ph adjusted water. check ph in run off water. Give it water only for for a few days, then re start nutrients at a lower dose.

[Cornsage]

This is helpful information, thank you all for your advice! We will test the pH of the water and then try watering with that for a while. In the meantime, should I trim off the damaged leaves, or leave them be?

Right now we feed at 1/8 per bottle, should we cut that down to 1/16 to dilute it more?

[Cornsage]

UPDATE: 7/25/2020 images included.

So first we upped our watering to 1 cup every other day (no Nutes) and while that seemed to keep the plants from drooping as much, they were still wilting pretty frequently and there was very little to no runoff.

While this definitely improved their appearance the fact that they were beginning to droop by the next day was still worrisome. So we took the chance and gave each plant 2 cups of water each yesterday (7/24/2020) and with this, we definitely had some runoff, but I can't quantify it. 10-20% maybe? We also brought the AC down by 2 degrees now it sits around 78 degrees.

They seemed to have perked up and have stayed that way since then. So, a win.

Anyway, we have not fertilized since 7/18/2020, I was hoping that by just giving freshwater that will help to flush it out. We will attempt to do a pH test soon.

If we need to add more ventilation to the pot, would that damage the roots at all if we stab into it? And should I cut off the damaged leaves? Only the lowest ones seem to be affected, and it probably would not hurt the plant to remove them so that the energy is reserved for the topmost ones.

Again, this is our first grow so we are expecting a learning curve and some correction for sure. But what do you more experienced experts think?

[growell]

untill the leaves turn fully yellow the plants still useing them there not deased and wont spread

[growell]

seems to only done half of reply i would leave them on

[Rwise]

Those big leaves are storage tanks, when the plant eats them they will turn yellow and fall off.